From 3a7d50924d190896053a20a783a758da237100bf Mon Sep 17 00:00:00 2001
From: Felix Roos <flix91@gmail.com>
Date: Tue, 7 Oct 2025 22:59:50 +0200
Subject: [PATCH] refactor: add op_precedence to express & with desugar_ops

---
 packages/mondo/mondo.mjs | 36 ++++++++----------------------------
 1 file changed, 8 insertions(+), 28 deletions(-)

diff --git a/packages/mondo/mondo.mjs b/packages/mondo/mondo.mjs
index d419eaff4..00a3b4011 100644
--- a/packages/mondo/mondo.mjs
+++ b/packages/mondo/mondo.mjs
@@ -21,14 +21,14 @@ export class MondoParser {
     close_curly: /^\}/,
     number: /^-?[0-9]*\.?[0-9]+/, // before pipe!
     // TODO: better error handling when "-" is used as rest, e.g "s [- bd]"
-    op: /^[*/:!@%?+-]|^\.{2}/, // * / : ! @ % ? ..
-    and: /^&/,
+    op: /^[*\/:!@%?+\-&]|^\.{2}/, // * / : ! @ % ? ..
     // dollar: /^\$/,
     pipe: /^#/,
     stack: /^[,$]/,
     or: /^[|]/,
     plain: /^[a-zA-Z0-9-~_^#]+/,
   };
+  op_precedence = [['*', '/', ':', '!', '@', '%', '?', '+', '-', '..'], ['&']];
   // matches next token
   next_token(code, offset = 0) {
     for (let type in this.token_types) {
@@ -151,30 +151,9 @@ export class MondoParser {
     }
     return children;
   }
-  desugar_ands(children) {
+  desugar_ops(children, types) {
     while (true) {
-      let opIndex = children.findIndex((child) => child.type === 'and');
-      if (opIndex === -1) break;
-      if (opIndex === children.length - 1) {
-        throw new Error(`cannot use & as last child.`);
-      }
-      if (opIndex === 0) {
-        throw new Error(`cannot use & as first child.`);
-      }
-      // convert infix to prefix notation
-      const op = { type: 'plain', value: children[opIndex].value };
-      const left = children[opIndex - 1];
-      const right = children[opIndex + 1];
-      const call = { type: 'list', children: [op, right, left] };
-      // insert call while keeping other siblings
-      children = [...children.slice(0, opIndex - 1), call, ...children.slice(opIndex + 2)];
-      children = this.unwrap_children(children);
-    }
-    return children;
-  }
-  desugar_ops(children) {
-    while (true) {
-      let opIndex = children.findIndex((child) => child.type === 'op');
+      let opIndex = children.findIndex((child) => child.type === 'op' && types.includes(child.value));
       if (opIndex === -1) break;
       const op = { type: 'plain', value: children[opIndex].value };
       if (opIndex === children.length - 1) {
@@ -285,9 +264,10 @@ export class MondoParser {
           // the type we've removed before splitting needs to be added back
           children = [{ type: 'plain', value: type }, ...children];
         }
-        children = this.desugar_ops(children);
-        children = this.desugar_ands(children);
-        // children = this.desugar_pipes(children, (children) => this.desugar_dollars(children));
+        // for each precendence group, call desugar_ops once
+        this.op_precedence.forEach((ops) => {
+          children = this.desugar_ops(children, ops);
+        });
         children = this.desugar_pipes(children);
         return children;
       }),